Hey, here are some answers to your questions:

They will fit a 98' DX coupe, yes they are adjustable .5'' to 3.0'', bought them from the audio connection in Columbia,MD for $300. Here is a link to the same product on eBay:

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2449108401

On Ground Control's website they are seperate categories, but for coilovers they are the same thing. It was not until 2001 that Honda used different suspension for the Si, all Honda's (even Del Sol) from 92-00 use the same suspension systems.